Malicious PDF — malware analysis report

Static analysis result for SHA-256 d440f6fed8081cac…

MALICIOUS

PDF

69.6 KB Created: 2021-09-10 19:15:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 8bc17faa97f1fac7175c6bb1b605d4ef SHA-1: 36802a393468cbec1afbc253e90a4dda58172249 SHA-256: d440f6fed8081cac6f0653142a9482d34d6b8f71c9529a4934e4eb67ca66fdd5
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file was flagged by multiple heuristics, including a critical ClamAV detection for 'Pdf.Phishing.Trojan' and an ML classifier indicating maliciousness. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic suggests it's part of a link farm designed to host numerous links on disposable domains. While no scripts were explicitly extracted, the presence of embedded URLs and the nature of the heuristics strongly indicate a phishing or malware distribution attempt, likely leveraging embedded JavaScript for malicious actions.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://cvenhancer.com/wp-content/plugins/super-forms/uploads/php/files/1c033cf6d27292e466ccfb28e8709aff/20310001085.pdf In PDF document text
    • https://kopari.hu/files/file/15022376513.pdfIn PDF document text
    • http://leebyunghun.kr/new/upload/board/files/dazigivozadojotafew.pdfIn PDF document text
    • https://thanaclusterwestgate.leaddeehub.com/userfiles/files/diniselixegumiwugedipux.pdfIn PDF document text
    • http://mya1fc.com/files/ckuploads/files/92597207707.pdfIn PDF document text
    • http://k12kos.com/ckfinder/userfiles/files/24219323177.pdfIn PDF document text
    • http://appextskihjthj.handysociality.com/upload/files/78472355653.pdfIn PDF document text
    • https://jlgardner.org/home/jlg/public_html/ckfinder/userfiles/files/redababepalimawizob.pdfIn PDF document text
    • http://arucax.am/user_images/file/levuteropax.pdfIn PDF document text
    • http://highspiritsmusic.com/ckfinder/userfiles/files/61968229987.pdfIn PDF document text
    • http://1666-3668.com/attach/userfiles/file/34736700631.pdfIn PDF document text
    • http://gekon.net/userfiles/file/79668738205.pdfIn PDF document text
    • https://dagvandearchitectuur.be/_files/file/pabebemenunatudaxazofux.pdfIn PDF document text
    • https://xinpayflow.com/ckfinder/userfiles/files/12563462652.pdfIn PDF document text
    • https://luatsuavina.com/userfiles/file/66082286543.pdfIn PDF document text
    • http://voszveszprem.hu/_user/file/beduxaxenir.pdfIn PDF document text
    • https://paloaltospeakerseries.com/wp-content/plugins/super-forms/uploads/php/files/69023062659676284c99a3db8c6dd2e9/80209357196.pdfIn PDF document text
    • https://rajaketiga.com/contents/files/64636913427.pdfIn PDF document text
    • https://makojudo.pl/zdjecia/fck/file/67129099474.pdfIn PDF document text
    • http://artattack-concerts.de/files/file/tigomiretevekuxor.pdfIn PDF document text
    • https://mytekas.com/UserFiles/file/62454875369.pdfIn PDF document text
    • http://claudiamelchior.it/images/file/53999245663.pdfIn PDF document text
    • http://winecellarkeeper.com/ckfinder/userfiles/files/65184105800.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=android+ratingbar+stylePDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b049.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB049 10660 bytes
SHA-256: d75c08de66381c65f4e90bd78587f33e01972c372e3a601d0eb25a716b923bb0
font_01_sfnt_off0000c8a7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC8A7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e0b9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE0B9 15712 bytes
SHA-256: 74b57a2bf23bddf40c9f4cb3fc67d3c588ccdd3a2af517692ac684f101113f7a